Hey guys,

I'm stumped. I've had the car smoke tested, came back negative for any leaks. Still having my fast/rough idle (varies from 1100 rpm all the way to 2k rpm at a stop light in neutral or with clutch in). I have check engine lights that I've tried to fix. I'm having the idle air control (idle higher than expected) code, another random code and then an O2 sensor code has been on and off (but they were replaced right before I bought the car). I don't have the diagnostic tool with me right now (in class), but I can definitely pull the codes if it will help get ideas flowing.

My exhaust tips also have a lot of carbon on them (presumably from running rich) and my fuel economy is terrible.

I have the WMW 17% pulley, DDMWorks CAI, and the Detroit Tuned Bypass Valve installed. Cleaned the intercooler, checked the boots for a good seal, cleaned the throttle body, seafoamed multiple times, nothing has changed.

Let me know if you guys have any ideas. Trying to fix it on my own, as I am on the college budget.

Thanks!

 

Could be anything from a failed throttle body to cracked intake tube between the throttle body and supercharger, improperly seated MAP sensor source on the intake tube, worn green gasket between the intake tube and supercharger, etc.

You need to have the car diagnosed by a qualified shop with proper scan tools, a generic reader doesn't give you enough information to quickly and easily diagnose a problem.

 

check the bypass valve. The spring in it can break and cause too much air as it cant close. so the car can up the idle to compensate for the leak. there is a video by Mod Mini about this on how to diagnose it. you can reach in and close the valve with your fingers or zip tie it closed to see if you car responds.

 

He's got a DT BPV, we have never had one of our valves have a spring fail. They may succumb to a few of the factory failings, but a broken spring isn't one of them.

Depending on the age of the valve, we have seen cracks develope around the butterfly rod that cause the butterfly to stick open or closed when they catch on the crack.

 

I just recently installed my DT bypass valve. Thanks for the recommendation though

 

Did you ever figure out the problem? I have a similar set up and having the a slightly high idle and a P0507 code and P1477 code. O2 sensors are new, MAP and TMAP sensors replaced, leak detection pump replaced and I even put in a DT BPV while I was at it so its not that. Looking for any other ideas to run down.